Common
bike chain
issues

When should you replace a bike chain?

Amateur, commuter, or pro cyclist… whoever you are, when you pile miles on your bike chain, it will wear out eventually, and at a certain point it will have to be replaced. If a bike chain slips off or falls off once, it can be easily put back on, but sometimes the bike chain will become so worn out that it must be replaced. 

A worn bike chain might be rusty or overstretched (often referred to as chain stretch or chain wear), which means repairing the chain is no longer an option. 

In general, a chain should be replaced every 3,000–5,000 km. By the time you’ve covered that kind of distance, the chain wear is likely noticeable on the chain itself, the cassette, and the chainrings.

This wear and tear is particularly important for e-bike chains, which are exposed to strong forces and constant strain. An average e-bike motor can achieve a torque between 50 and 120 Nm (Newton metres) - that’s comparable to the motor of a motorcycle.

To help prolong the life of your bike chain, there are a few common issues and bike chain maintenance tips to keep in mind. Read on for our complete guide to looking after your electric bike chain.

Common bike chain issues

Vigorous pedalling, weather conditions, or improper gear-shifting skills can significantly increase the wear and tear on a bike chain. Visible signs of wear or damage can be spotted with regular inspections before a ride. Rust is a common issue that can sometimes be treated with removers such as WD-40.

One of the primary ways to spot a worn-out bike chain is by the noise it makes. Ideally, when pedalling, the drivetrain and the bike chain are silent. When the bike chain does make a squeaking noise or cracking sound while pedalling, you should inspect the bike chain, the drivetrain, and the gearshift system. 

If it’s cracking, it might have come loose. If it’s squeaking, try to clean the bike chain (more on that below) and lubricate it again. A squeaky and poorly maintained bike chain leads to poor shifting, lost power efficiency, and a bad all-round cycling experience.

As soon as you experience a gritty feel and it becomes rougher and more difficult to pedal normally, it is time to check your bike chain and repair, clean, or lubricate it before taking your next ride. 

A poorly maintained and worn-out bike chain can also easily come off during a ride or even break. Additionally, the sprockets and chainrings on the crank will suffer significant wear and tear if you’re cycling on a broken or damaged chain. If that happens, you’ll need to replace the chain and possibly even the entire drivetrain. 

Rusty bike chains

While you’re out riding your bike, the bike chain is continuously exposed to dirt and water. This can cause rusty spots on the bike chain that can impact performance.

To avoid rust buildup, make sure to keep the bike chain clean and well-lubricated. If you’ve been out riding in particularly wet weather, make sure to thoroughly dry the chain before applying lubricant.

How you deal with a rusty bike chain will depend on the level of rust. If your bike chain is severely rusted, it’s best to be on the safe side and replace it with a new bike chain as soon as possible. Badly rusted bike chains can be dangerous, but they can also speed up wear and tear on your chainrings and sprockets.

Bike chains that are just starting to rust or have minimal damage can be cleaned with lime juice or WD-40 to make them shiny and rust-free again. After cleaning the bike chain, don’t forget to check the tension and lubricate the bike chain before your next ride.

Loose bike chains

Overstretching can also be an issue for bike chains; - telltale signs include inconsistent and slow shifting, or the bike chain slipping over the top of the cog and skipping one or more teeth. With a hub or shift gear, the chain will also fall off much faster.

A bike chain that’s too loose will affect the gears, which will no longer function properly. As a result, the bike chain can slip, come off, or even break while riding. 

Because of the weight of the bike itself and the high speeds sometimes reached during a ride, bikes are exposed to heavy forces and loads. A strong chain is a crucial part of the bike and is made of durable stainless steel to add to its stability. The service life of a bike chain is mainly dependent on individual wear and tear and on the standard of care and maintenance.

For more bike maintenance tips, head to our Electric Bike Knowledge Hub.